How to Write a Laboratory Report

Since scientific research of any type loses value if its results are not communicated to others, a lab report is written to thoroughly describe the research process, explain why and how it was done, what the findings were, and whether the findings matched the expected results. Stated succinctly, in a lab report, you provide accurate and factual information about research.

Steps for Writing a Lab Report

Determine the structure of your lab report. Lab reports consist of five sections: an abstract, an introduction, an experimental section, results, and a discussion.

Write the introduction first. Its main goal is to introduce the experiment to the reader and explain its objectives and its significance. Formulate the hypothesis and the prediction of the experiment in a concise, clear manner and define terminology. You can also provide readers with the background needed for them to understand the experiment.

Write the results. Provide readers with data that was obtained during experiments and analyze it.

Proceed to the discussion section. Here you must interpret the results, state whether your findings were consistent with the hypothesis, discuss their significance, and acknowledge possible sources of errors. You can also introduce possible alternative explanations for your findings and point out any flaws in the study.

Write the experimental section. In it, you must list methods and materials that were used during the experiment. It doesn’t necessarily need to be detailed; however, it must contain enough information to allow another person to replicate the experiment. Significant observations made during laboratory work should also be included in this section.

Write the abstract. Though it is the first part of a lab report, it is more convenient to write the abstract when you have all the important information systematized. The abstract is not detailed. It is a concise summary of the entire work, which serves to briefly introduce the results of the experiment and intrigue the reader.

List the citations you used. Usually, MLA or APA bibliography formats are used. Make a title page.

Topic Selection

Laboratory reports are written for experiments and conducted by students. Therefore, the topic of a lab report depends on the discipline and on the nature of the experiment that has been conducted. For example, lab reports can be written for such experiments as:

conducting a Briggs-Rauscher reaction

qualitative reactions to sulfate, carbonate, silicate ions

the adsorption of nitrogen dioxide by carbon

determining the length of a electromagnetic wave with the help of Lecher’s method

the interaction of electromagnetic waves with matter

Key Points to Consider

The title of your lab report should be brief and concise but still remain an accurate reflection of its content. The title is the first aspect of your lab report readers see, so it must help readers understand whether your report is relevant to their scientific interests or not.

An easy way to check the quality of your lab report is to ask yourself whether someone could successfully replicate the experiment you’ve conducted using only the information from your report.

Lab reports should follow a standard format so that readers can easily find the information they need immediately without searching for it in the whole report.

Readers don’t necessarily read the lab report in order. They read the abstract first to see what the paper is about. If they find it intriguing, or if it corresponds with their scientific interests, the readers will apparently skip to the conclusions. And in the case of the conclusions being intriguing, or especially unexpected, the reader will most likely read the rest of the report.

Lab reports must be written in a strict scientific style. This means, first of all, you should limit the use of personal pronouns, emotional words, and inexact terms. Also, it is necessary to be concise, since long sentences and excessive word quantities may confuse the reader. Therefore, use one word instead of two where possible and try to break long sentences into smaller ones.

Dos and Don’ts

Dos

Do keep in mind that writing a lab report is an individual assignment. Give credits when appropriate, but remember that despite whether or not you have a lab partner, the work you do and the report you write must be your own.

Do write in complete sentences and avoid using contractions. Mind your grammar and punctuation. Using passive voice will make the text of the report look more impersonal and objective.

Do avoid using meaningless phrases. Compare these two sentences: “As it is shown in Figure 3, radium decay rate is proportional to its amount” and “Radium decay rate is proportional to its amount (Figure 3).” Your language must be concise and to the point.

Do enumerate all equations, except simple ones. Also, do number and title all tables, graphs, and figures. Do place each graph on a single sheet of paper.

Do use tables to show correlations that are present in the data or in those cases when you need to place large amounts of data in the text.

Do keep the abstract of your lab report short and avoid including references in it. Lab reports are written in 120 to 250 words. Additionally, assignment instructions often specify requirements for a word limit. If not, a sound idea would be to read other lab reports to see how long abstracts usually are.

Don’ts

Don’t write equations in the body of the text. Give each equation its own line. An exception can be made only for simple, short equations that you will no longer need.

Don’t thoughtlessly copy all the data you’ve collected during your research to the report. Think about what results are important and need to be included and what could be omitted.

Don’t include any references and abbreviations in the abstract. Trying to explain data or describe materials and methods you were using during the experiment in this section of a lab report is an imprudent idea.

Don’t include information from external sources you do not cite in your report.

Don’t explain errors in the results with a human factor or miscalculation. Everyone knows people make mistakes, and that various misconceptions can take place. Also, it is understood that calculation devices can malfunction. However, as a person conducting a scientific work, you are responsible for choosing calculation techniques that minimize or exclude the possibility of errors.

Common Mistakes When Writing a Lab Report

- Trying to write a whole lab report the day before it must be submitted. You leave almost no time to analyze and interpret your results properly.

- Rounding off too early in calculations. This procedure should be done at the end of your calculations, when you already have the result. If you round off insignificant figures in the beginning, your data will probably be incorrect.

- Confusing analyses with interpretation. Analyses assume you’ve figured out what the data received during the experiment shows and what trends are present in them. Analyses are basically reported in the results section. Interpretation implies speculating on the data and explaining what they mean. Interpretation is carried out in the discussion section.

- Using the word “data” as a singular noun. “Data” is a plural form of “datum.” Therefore, it is correct to write “data were received,” and “the datum is reliable.”

- Confusing the meaning of “i.e.” and “e.g.” abbreviations. The “i.e.” abbreviation is from the Latin phrase, “id est,” which means “that is.” You should use this abbreviation if you want to provide readers with an explanation of the material. The “e.g.” abbreviation is from “exampli gratia,” which means “for example” and is used to illustrate the material.